Combine yeast, sugar, water and 1 tbsp. flour in a bowl. Mix well, cover, and wait until it rises.

In another bowl, mix 3 cups flour, melted margarine, salt, sugar and egg yolks. Add yeast mixture to this and mix. Slowly add water/milk while stirring. When batter is smooth, cover the bowl with a towel and let it sit and rise.

Make the doughnuts:

After the batter has risen, pour it onto a floured surface and roll it out. Use a glass with a small opening to cut out circles of the dough. Lace a drop of jelly in the middle of each circle, and then cover with another circle of dough. Make sure that 2 circles attach well to form a closed ball with jelly in the middle. Cover the doughnuts with a towel and let rise

Frying doughnuts:

Heat oil in a deep pot to 375 degrees. Drop the doughnuts into the oil and fry on both sides until brown. Remove with a slotted spoon and sprinkle with powdered sugar.